/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.flink.streaming.connectors.kinesis.model;

import org.apache.flink.annotation.Internal;
import org.apache.flink.util.Preconditions;

import com.amazonaws.services.kinesis.model.Shard;

/**
 * A wrapper class that bundles a {@link StreamShardHandle} with its last processed sequence number.
 */
@Internal
public class KinesisStreamShardState {

    /** A handle object that wraps the actual {@link Shard} instance and stream name. */
    private StreamShardHandle streamShardHandle;

    /** The checkpointed state for each Kinesis stream shard. */
    private StreamShardMetadata streamShardMetadata;

    private SequenceNumber lastProcessedSequenceNum;

    public KinesisStreamShardState(
            StreamShardMetadata streamShardMetadata,
            StreamShardHandle streamShardHandle,
            SequenceNumber lastProcessedSequenceNum) {

        this.streamShardMetadata = Preconditions.checkNotNull(streamShardMetadata);
        this.streamShardHandle = Preconditions.checkNotNull(streamShardHandle);
        this.lastProcessedSequenceNum = Preconditions.checkNotNull(lastProcessedSequenceNum);
    }

    public StreamShardMetadata getStreamShardMetadata() {
        return this.streamShardMetadata;
    }

    public StreamShardHandle getStreamShardHandle() {
        return this.streamShardHandle;
    }

    public SequenceNumber getLastProcessedSequenceNum() {
        return this.lastProcessedSequenceNum;
    }

    public void setLastProcessedSequenceNum(SequenceNumber update) {
        this.lastProcessedSequenceNum = update;
    }

    @Override
    public String toString() {
        return "KinesisStreamShardState{"
                + "streamShardMetadata='"
                + streamShardMetadata.toString()
                + "'"
                + ", streamShardHandle='"
                + streamShardHandle.toString()
                + "'"
                + ", lastProcessedSequenceNumber='"
                + lastProcessedSequenceNum.toString()
                + "'}";
    }

    @Override
    public boolean equals(Object obj) {
        if (!(obj instanceof KinesisStreamShardState)) {
            return false;
        }

        if (obj == this) {
            return true;
        }

        KinesisStreamShardState other = (KinesisStreamShardState) obj;

        return streamShardMetadata.equals(other.getStreamShardMetadata())
                && streamShardHandle.equals(other.getStreamShardHandle())
                && lastProcessedSequenceNum.equals(other.getLastProcessedSequenceNum());
    }

    @Override
    public int hashCode() {
        return 37
                * (streamShardMetadata.hashCode()
                        + streamShardHandle.hashCode()
                        + lastProcessedSequenceNum.hashCode());
    }
}
